The present invention relates to novel pyrimidyl derivatives, to a process for their manufacture, pharmaceutical compositions containing them and their manufacture as well as the use of these compounds as pharmaceutically active agents.
Protein kinases (“PKs”) are enzymes that catalyze the phosphorylation of hydroxy groups on tyrosine, serine and threonine residues of proteins (Hunter, T., Cell 50 (1987) 823-829). The consequences of this seemingly simple activity are staggering; cell growth, differentiation and proliferation, i.e., virtually all aspects of cell life in one way or another depend on PK activity. Furthermore, abnormal PK activity has been related to a host of disorders, ranging from relatively non-life threatening diseases such as psoriasis to extremely virulent diseases such as glioblastoma (brain cancer).
The PKs can be conveniently broken down into two classes, the protein tyrosine kinases (PTKs) and the serine-threonine kinases (STKs).
One of the prime aspects of PTK activity is their involvement with growth factor receptors. Growth factor receptors are cell-surface proteins. When bound by a growth factor ligand, growth factor receptors are converted to an active form which interacts with proteins on the inner surface of a cell membrane. This leads to phosphorylation on tyrosine residues of the receptor and other proteins and to the formation inside the cell of complexes with a variety of cytoplasmic signaling molecules that, in turn, effect numerous cellular responses such as cell division (proliferation), cell differentiation, cell growth, expression of metabolic effects to the extracellular microenvironment, etc. For a more complete discussion, see Schlessinger, J. and Ullrich, A., Neuron, 9 (1992) 383-391, which is incorporated by reference, including any drawings, as if fully set forth herein.
Growth factor receptors with PTK activity are known as receptor tyrosine kinases (“RTKs”). They comprise a large family of transmembrane receptors with diverse biological activity. At present, at least nineteen (19) distinct subfamilies of RTKs have been identified. An example of these is the subfamily designated the “HER” RTKs, which include EGFR (epidermal growth factor receptor), HER2 (human epidermal growth factor receptor 2), HER3 and HER4. These RTKs consist of an extracellular glycosylated ligand binding domain, a transmembrane domain and an intracellular cytoplasmic catalytic domain that can phosphorylate tyrosine residues on proteins.
Another RTK subfamily is referred to as the platelet derived growth factor receptor (“PDGFR”) group, which includes PDGFR alpha, PDGFR beta, colony-stimulating factor 1 receptor (CSF-1R), c-kit and flt-3. These receptors consist of glycosylated extracellular domains composed of 5 immunoglobin-like loops and an intracellular domain wherein the tyrosine kinase domain is interrupted by a kinase inert domain.
Another group which, because of its similarity to the PDGFR subfamily, is sometimes subsumed into the latter group is the fetal liver kinase (“Flk”) receptor subfamily. This group, containing extracellular immunoglobulin loops made up of kinase insert domain receptor/fetal liver kinase-1 (KDR/Flk-1), and fins-like tyrosine kinase 1 (Flt-1 and Flt-4). The human analogue of FLK-1 is the kinase insert domain-containing receptor KDR, which is also known as vascular endothelial cell growth factor receptor 2 or VEGFR-2, since it binds VEGF with high affinity.
Of the three PTK (protein tyrosine kinases) receptors for VEGFR identified VEGFR-1 (Flt-1); VEGRF-2 (Flk-1 or KDR) and VEGFR-3 (Flt-4), VEGFR-2 is of peculiar interest.
The process of angiogenesis is the development of new blood vessels, generally capillaries, from pre-existing vasculature. Angiogenesis is defined as involving (i) activation of endothelial cells; (ii) increased vascular permeability; (iii) subsequent dissolution of the basement membrane and extravasations of plasma components leading to formation of a provisional fibrin gel extracellular matrix; (iv) proliferation and mobilization of endothelial cells; (v) reorganization of mobilized endothelial cells to form functional capillaries; (vi) capillary loop formation; and/or (vii) deposition of basement membrane and recruitment of perivascular cells to newly formed vessels.
Normal angiogenesis is activated during tissue growth, from embryonic development through maturity, and then enters a period of relative quiescence during adulthood.
Normal angiogenesis is also activated during wound healing, and at certain stages of the female reproductive cycle. Inappropriate or pathological angiogenesis has been associated with several disease states including various retinopathies; neuropathologic diseases like stroke, Alzheimer's disease and motor neuron disease, ischemic disease; atherosclerosis; chronic inflammatory disorders; rheumatoid arthritis, and cancer. The role of angiogenesis in disease states is discussed, for instance, in Fan, T. P., et al., Trends in Pharmacol Sci. 16 (1995) 57-66; Folkman, J., Nature Medicine 1 (1995) 27-31, and Greenberg, D. A., et al., Nature 438 (2005) 954-959.
It has been proposed that various receptor-type tyrosine kinases, and the growth factors binding to them, play a role in angiogenesis, although some may promote angiogenesis indirectly (Mustonen, T., et al., J. Cell Biol. 129 (1995) 895-898). One of these receptor-type tyrosine kinases is fetal liver kinase 1, also referred to as FLK-1. The human analogue of FLK-1 is the kinase insert domain-containing receptor KDR, which is also known as vascular endothelial cell growth factor receptor 2 or VEGFR-2, since it binds VEGF with high affinity. Finally, the murine version of this receptor has also been called NYK (Oelrichs, R. B., et al., Oncogene 8 (1993) 11-15). VEGF and KDR are a ligand-receptor pair which plays a vital role in the proliferation of vascular endothelial cells and the formation and sprouting of blood vessels, referred to as vasculogenesis and angiogenesis respectively.
Angiogenesis is characterized by excessive activity of vascular endothelial growth factor (VEGF). VEGF actually consists of a family of ligands (Klagsbrun, M., et al., Cytokine & Growth Factor Reviews 7 (1996) 259-270). VEGF binds the high affinity membrane-spanning tyrosine kinase receptor KDR and the related fms-like tyrosine kinase-1, also known as Flt-1 or vascular endothelial cell growth factor receptor 1 (VEGFR-1). Cell culture and gene knockout experiments indicate that each receptor contributes to different aspects of angiogenesis. KDR mediates the mitogenic function of VEGF, whereas Flt-1 appears to modulate non-mitogenic functions, such as those associated with cellular adhesion. Inhibiting KDR thus modulates the level of mitogenic VEGF activity. In fact, tumor growth has been shown to be susceptible to the antiangiogenic effects of VEGF receptor antagonists (Kim, K. J., et al., Nature 362 (1993) 841-844).
Solid turnouts can therefore be treated with tyrosine inhibitors since these tumors depend on angiogenesis for the formation of the blood vessels that are necessary to support their growth. These solid turnouts include monocytic leukaemia, carcinomas of the brain, urogenital tract, lymphatic system, stomach, larynx and lung, including lung adenocarcinoma and small cell lung carcinoma. Further examples include carcinomas in which overexpression or activation of Raf-activating oncogenes (for example, K-ras, erb-B) is observed. Such carcinomas include pancreatic and breast carcinoma. Inhibitors of these tyrosine kinases are therefore suitable for the prevention and treatment of proliferative diseases caused by these enzymes.
The angiogenic activity of VEGF is not limited to tumors. VEGF accounts for the angiogenic activity produced in several disease states including various retinopathies (e.g. in or near the retina in diabetic retinopathy), neuropathologic diseases like stroke, Alzheimer's disease and motor neuron disease, ischemic disease; atherosclerosis; chronic inflammatory disorders; rheumatoid arthritis, and cancer. The role of angiogenesis in disease states is discussed, for instance, in Fan, T. P., et al., Trends in Pharmacol Sci. 16 (1995) 57-66; Folkman, J., Nature Medicine 1 (1995) 27-31, and Greenberg, D. A., et al., Nature 438 (2005) 954-959.
A more complete listing of the known RTK subfamilies is described in Plowman, G. D., et al., Drugs News and Perspectives 7 (1994) 334-339, which is incorporated by reference, including any drawings, as if fully set forth herein.
In addition to the RTKs, there also exists a family of entirely intracellular PTKs called “non-receptor tyrosine kinases” or “cytoplasmic tyrosine kinases.” This latter designation, abbreviated “CTK,” will be used herein. CTKs do not contain extracellular and transmembrane domains. At present, over 24 CTKs in 11 subfamilies (Src, Frk, Btk, Csk, Abl, Zap70, Fes, Fak, Jak, LIMK and Ack) have been identified. The Src subfamily appear so far to be the largest group of CTKs and includes Src, Yes, Fyn, Lyn, Lck, Blk, Hck, Fgr, and Yrk. A further important group of CTKs is the Abl family including Abl and Arg. For a more detailed discussion of CTKs, see Bolen, J. B., Oncogene 8 (1993) 2025-2031, which is incorporated by reference, including any drawings, as if fully set forth herein.
The serine/threonine kinases, STKs, like the CTKs, are predominantly intracellular although there are a few receptor kinases of the STK type. STKs are the most common of the cytosolic kinases; i.e., kinases that perform their function in that part of the cytoplasm other than the cytoplasmic organelles and cytoskeleton. The cytosol is the region within the cell where much of the cell's intermediary metabolic and biosynthetic activity occurs; e.g., it is in the cytosol that proteins are synthesized on ribosomes. The STKs include CDk2, Raf, the ZC family of kinases, the NEK family of kinases, and BUB 1.
The coordinated action of both protein kinases and phosphatases controls the levels of phosphorylation and, hence, the activity of specific target proteins. One of the predominant roles of protein phosphorylation is in signal transduction, where extracellular signals are amplified and propagated by a cascade of protein phosphorylation and dephosphorylation events, e.g. in the ras/raf pathway.
Activated Ras is necessary for the activation of the c-raf-1 proto-oncogene, but the biochemical steps through which Ras activates the Raf-1 protein (Ser/Thr) kinase are now well characterized. It has been shown that inhibiting the effect of active ras by inhibiting the rat kinase signaling pathway by administration of deactivating antibodies to raf kinase or by co-expression of dominant negative raf kinase or dominant negative MEK, the substrate of rat kinase, leads to the reversion of transformed cells to the normal growth phenotype see: Daum, G., et al., Trends Biochem. Sci. 19 (1994) 474-480; Fridman, M., et al., J. Biol. Chem. 269 (1994) 30105-30108. Kolch, W., et al., Nature 349 (1991) 426-428, and for review, Weinstein-Oppenheimer, C. R., et al., Pharm. & Therap. 88 (2000) 229-279.
RTKs, CTKs and STKs have all been implicated in a host of pathogenic conditions including, significantly, cancer. Other pathogenic conditions which have been associated with PTKs include, without limitation, psoriasis, hepatic cirrhosis, diabetes, angiogenesis, fibrosis, restenosis, ocular diseases, rheumatoid arthritis and other inflammatory disorders, immunological disorders such as autoimmune disease, cardiovascular disease such as atherosclerosis and a variety of renal disorders.
With regard to cancer, two of the major hypotheses advanced to explain the excessive cellular proliferation that drives tumor development relate to functions known to be PK regulated. That is, it has been suggested that malignant cell growth results from a breakdown in the mechanisms that control cell division and/or differentiation. It has been shown that the protein products of a number of proto-oncogenes are involved in the signal transduction pathways that regulate cell growth and differentiation. These protein products of proto-oncogenes include the extracellular growth factors, transmembrane growth factor PTK receptors (RTKs), cytoplasmic PTKs (CTKs) and cytosolic STKs, discussed above.
In view of the apparent link between PK-related cellular activities and wide variety of human disorders, it is no surprise that a great deal of effort is being expended in an attempt to identify ways to modulate PK activity. Some of these have been made to identify small molecules which act as PK inhibitors.
WO 2002/032872 describes nitrogenous aromatic ring compounds useful as PK inhibitors. WO 2003/099771 and WO 2005/051366 relate to diaryl urea derivatives useful for the treatment of PK inhibitor dependent diseases.